Rotatably mounted sear safety



A rink-- March 26, 1957 c. cooK 2,786,293

ROTATABLY MOUNTED SEAR SAFETY Filed April 22, 1953 HIM IIIIIATIIIIIII/lli 'IIIIIIII l I' I III.

. V INVENTOR. 5o LmrErL ELE'cmk B MM+ZM Q flTTOENEY'S United States Patent ROTATABLY MOUNTED SEARSAFE Loren C. Cook, Rodeo, Calif.

Application April 22, 1953, Serial No. 350,542

1 Claim. (Cl. 42-70) (Granted under Title 35, U. S. Code- (1952),'sec. 266) The invention described hereinmaybemanufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to automatic firearms and more particularly to a combined firing and safety mechanism therefor.

One object of this invention is to provide in a firearm a firing mechanism which is simple in design; economical and durable in constructiompositive in action, and which may be assembled and disassembled easily and quickly.

A particular object of this invention is to provide in a firearm an improved firing and safety mechanism wherein a single spring simultaneously providesresilient bias to the trigger, the sear, and the safety. Besides the aforementioned functions the same spring 'also serves as the means for retaining the sear pin, the safety,-a-nd the trigger pin in the firearm.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from a description of a preferred embodiment as shown in the accompanying drawings in which:

Fig. l is a fragmentary side view .of a firearminlongitudinal section showing the safety .in the inoperative position and the sear in the cockedposition;

Fig. 2 is a section on line 2-2 of Fig. 1;

Fig. 3 is a view similar to Fig. 2 but. showing the safety rotated tothe operative position;

Fig.4 is a section on line 4--4 of Fig. 2;

Fig. 5 is a section on line 5-5 of Fig. 3;

Fig. 6 is a cross-sectional view taken along line 6--6 in Fig. 1 showing the manner in which the sear is mounted in the firearm;

Fig. 7 is a fragmentary sectional top view across the housing showing the trigger, the trigger pin, and part of the sear; and

Fig. 8 is a perspective view of the sear.

As illustrated in the drawings, the firearm herein utilized to explain the present invention is provided with a channel-like housing 2 having suitable, opposed longitudinal ways 3 therein for guiding the reciprocal movements of a member of the breech mechanism (not shown). Attached to the underside of the forward end of housing 2 is a trigger guard 8. Mounted transversely through housing 2 immediately above trigger guard 8 is a cylindrical pin 4 having a centrally located reduced diameter portion 5 and a pair of annular shoulders 7 formed by the junctions of reduced diameter portion 5 with the larger end portions of pin 4. Pivotally mounted on reduced diameter portion 5 is a trigger 6 having a transverse mounting hole 39 of suflicient diameter to pass over the larger end portions of pin 4. Trigger 6 is also provided with a rearwardly extending actuator arm 11 and a finger piece which extends downwardly through a vertical slot 9 provided through housing 2 and within trigger guard 8.

A longitudinally formed sear 12 is pivotally mounted within housing 2 rearwardly of trigger 6 by means of a ice transverse cylindrical pin 13. The forward end of sear 12 rests on actuator arm 11 of trigger 6 and the opposite end ofthe sear, indicated by 15 and hereinafter referred to as the head, terminates'in the vicinity of a rotatably mounted safety device 16 with which it coacts in a manner to belater described. Centrally located in sear 12 is a vertical slot 14 which is transversely intersected by pin 13 as best shown in Figs. 1 and 6. Within the confines of slot 14, pin 13'is of reduced diameter as shown at 17 and such reduced portion forms at its junc tions with the larger diametrical portions of the pin, theannular shoulders 18. Encircling reduced diameter portion 17, between shoulders 18, is the coil portion 19 of a spring 20 having a forwardly extending arm 21, which rests on the-upper side of scar 12 forwardly of slotI4, and a relatively longer arm 22, that extends along the underside of scar 12 rearwardly of slot 14 to bear resiliently upon safety 16 in a manner to be described later. A recess 23 is provided along the underside of scar 12 to receive arm 22.

"Safety comprises a rod member 24 which passes through a hole'25 provided in one side of housing 2 and which is rotatably seated in a transverse arcuate recess 38 provided in the base of housing 2. One end of rod member 24 is provided with serrated operating knob 26. Adjacent the opposite end of rod 24 is an annular groove 27 that mates with a chordal rib 28 projecting upwardly within arcuate recess 38. The upper portion of hole 25 is slightly'beveled as shown at 37 and thereby permits rod portion 24 to be tilted sufficiently during assembly into housing 2 to clear rib 28 prior to engagement thereofby groove 27. The resilient pressure of arm 22 of spring 20 maintains safety 16 in recess 38 of housing 2 by insuring the engagement of groove 27 with rib 28.

Provided'in the lower portion of scar head 15 is an arcuate cut-outportion 30, which corresponds to the contour of'rod member 24, and-a substantially rectangular lug 31 formed'therein. A slot 32 is provided on rod 24 to receive lug 31 when operating handle26 of safety 16 in 'fire position and thereby permits unobstructed downward movement of head 15 of sear 12, asbest shown'in Figs. 2 and 4. When operating knob 26pisrotated approximately to the safe position, asbest' shown in'Fi'gsu3and 5, the downward'movement of head 15 is prevented by the solid portion of rod portion 24- engaging lug 31. w

Also provided on rod 24 is a cut-out portion 33 having a planar base 34 so locatedthat it is fully engaged by arm 22 of spring 20 when safety 16 is in fire position, as best shown in Figs. 2 and 4, and an adjacent smaller cut-out portion 35 having a planar base 36 that is engaged by arm 22 in a like manner when the safety is in safe position, as best shown in Figs. 3 and 5. Since cut-out portion 33 is much deeper than portion 35, safety 16 can be rotated more easily into the fire position. Arm 22, resiliently resting on either of planar bases 34 and 36, acts as a detent to hold safety 16 in either safe or fire position.

It is obvious that the resilient mounting of arm 22 upon rod 24 tensions spring 20 and produces a cor responding resilience of arm 21 which presses the forward end of scar 12 downwardly against actuator arm 11 of trigger 6 thus swinging finger piece 10 forwardly until stopped by the lower side of actuator arm 11 contacting the base of housing 2. Further, the pressure of sear 12 on actuator arm 11 of trigger 6 resiliently maintains contact of a portion of the interior surface of mounting hole 39 in trigger 6 with a portion of the surface of reduced diameter portion 5 of pin 4. As a result of such engagement, shoulders 7 of pin 4 serve to retain pin 4 in housing 2 by preventing transverse movement therein. The pivotal movement imparted to sear 12 by spring arm 21 causes head 15 to project upwardly into the path of the movable member of the breech mechanism (not shown) mounted on ways 3 and engage a suitable recess therein for holding such movable member during the counter-recoiling movement in cocked position. In addition, the tension of spring 20 urges coil portion 19 thereof resiliently upward against the surface of reduced diametrical portion 17 of pin 13 whereby shoulders 18 serve to restrain lateral movement of the pin and thereby retain it in housing 2.

The operation of the firing mechanism is as follows: With safety 16 in fire position, so that slot 32 thereof is in position to receive lug 31 of sear 12, the weapon is fired by pulling finger piece of trigger 6 rearwardly. The pull on finger piece 10 will move actuator arm 11 upwardly against the forward end of sear 12 causing the sear to rock on pin 13 and releasably withdraw head 15 from the engaged member of the breech mechanism, allowing it to go forward and fire a chambered cartridge. The weapon will continue to fire as long as there are cartridges in the magazine or until pressure is released from finger piece 10 of trigger 6. When the pressure on finger piece 10 is released, the tension in spring arm 21 will rock sear 12 to bring head 15 again into the path of the movable breech member for engagement therewith.

From the foregoing, it is readily apparent that the firing mechanism and safety device of this invention is characterized by a simplicity of design, ruggedness of structure, economy of manufacture, and positiveness of action. It will be noticed that single spring acts upon sear 12 and thereby on trigger 6. Further, the same spring acts as a detent to lock safety 16 in fire and safe positions and also serves to retain trigger pin 4, sear pin 13, and safety 16 in housing 2. Furthermore, it is readily apparent that the trigger mechanism and safety device of the present invention, may be disassembled quickly and easily by the removal of sear pin 13 which releases the tension on spring 20, and frees the parts for disassembly. Assembly is accomplished with equal ease and rapidity.

I claim:

A firing mechanism for a firearm having a breech member reciprocable between a battery and a cocked position, said firing mechanism comprising a trigger housing, a pin provided with a central reduced diameter portion and mounted transversely through said trigger housing,

fit

a trigger mounted on said reduced diameter portion for pivotal movement and for restraining said pin from lateral movement, an actuator arm extending rearwardly from said tn'gger, a shaft mounted transversely through said trigger housing rearwardly of said pin and provided with a central reduced diameter portion disposed between a pair of annular shoulders, a linear sear pivotally mounted between the ends thereof on said shaft, a forward end portion of said sear having engagement with the top side of said actuator arm for actuation thereby when said trigger is pivoted, a rearward head portion on said sear for releasably engaging the breech member in the cocked position, a vertical slot extending through said sear for communication with the reduced diameter portion of said shaft, a laterally disposed safety mounted in an arcuate recess in said trigger housing for rotation between a firing position and a safety position wherein said sear is blocked thereby from releasing the breech member, a chordal rib in said arcuate recess cooperable with an annular groove in said safety for restraining said sear in said trigger housing, a spring having a coil portion receivable by said slot for mounting on the reduced diameter portion of said shaft and being cooperable with said annular shoulders for releasably retaining said shaft in retaining said trigger in the reduced diameter portion of said pin and for pivoting said head portion upwardly for engagement with the breech member.

References Cited in the file of this patent UNITED STATES PATENTS 2,233,504 1 Young Mar. 4, 1941 2,453,683 Caldow Nov. 9, 1948 2,505,760 -Garand May 2, 1950 2,512,638 Gaidos June 27, 1950 2,533,283 Pierce Dec. 12, 1950 2,590,862 Hoppert Apr. 1, 1952 2,654,175 Hansen Oct. 6, 1953 

